ObDereferenceObjectDeferDelete function (wdm.h)

Article
02/22/2024

The ObDereferenceObjectDeferDelete routine decrements the reference count for the given object, checks for object retention, and avoids deadlocks.

Syntax

void ObDereferenceObjectDeferDelete(
  [in] PVOID Object
);

Parameters

[in] Object

A pointer to the body of the object.

Return value

None

Remarks

ObDereferenceObjectDeferDelete is similar to ObDereferenceObject except that, when the reference count of the object reaches zero, the object manager passes the object deletion request to a worker thread. Therefore, the deletion later occurs at IRQL = PASSIVE_LEVEL.

Use ObDereferenceObjectDeferDelete for any object when the immediate deletion by the current thread of the object (by using ObDereferenceObject) might result in a deadlock.

For example, such a deadlock can occur if ObDereferenceObject is used to dereference a Kernel Transaction Manager (KTM) object when a higher level driver on the driver stack is holding a lock.

To avoid such deadlocks, use ObDereferenceObjectDeferDelete instead of ObDereferenceObject to dereference KTM object.

For information about object permanence and attributes, see ObDereferenceObject.

Requirements

Requirement	Value
Target Platform	Universal
Header	wdm.h (include Fltkernel.h, Ntifs.h)
Library	NtosKrnl.lib
DLL	NtosKrnl.exe
IRQL	IRQL <= DISPATCH_LEVEL